It used to be, and maybe it still is that way, that after a call you could dial *1157 and their number would go into some sort of database. After a good amount of calls have been recorded, authorities could then be called upon to pursue.
Not sure if this would bother the guys in India, but maybe the people that own the toll number could exert some influence over them.

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It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D